An 18-year-old woman is now fighting for her life in the hospital after a chain reaction crash on the Hutchinson River Parkway overnight.

The chain reaction crash happened around 3:45 a.m. just before Exit 1C on the Hutchinson River Parkway going North. And that woman that is seriously hurt was a passenger on a moped before it was struck.

Police told News 12 that the woman was on a moped with a man-- when a Honda Pilot driving behind stepped on the breaks to avoid the moped--- that led to a third car to collide with the Honda Pilot-- causing severe damages.

We're told at some point the two people on the moped fell off.

And the man driving the moped took off on the scooter. Leaving the 18-year-old woman lying on the parkway. The people in the Honda Pilot and the third car were taken to the hospital and are expected to be okay. But again that 18-year-old woman is fighting for her life.

At the scene there was blood covering a portion of the left lane and bloody t-shirt lying in the grass.

Leading to the off ramp, you can see a black bumper and deep tire marks in the mud.

This morning, NYPD had all lanes of the parkway closed off from Exit 1B to where the accident happened at 1C for over four hours causing a major backup taking over 40 minutes to get past one exit.

The parkway has since reopened as cars are driving over broken glass and car parts lying in the road from the accident. The NYPD says they are still investigating as they look for the driver of the moped, who left his passenger lying in the roadway.